Hack around broken PluginManager listing duplicate plugins.

Issue CLIENT-335

Change-Id: Ieabc6957c7b46fa72e5a752f77b789d5da7dce7d
Reviewed-on: http://gerrit.dmdirc.com/2407
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>

src/com/dmdirc/addons/ui_swing/components/addonpanel/PluginPanel.java

@@ -79,7 +79,9 @@ public class PluginPanel extends AddonPanel implements ActionListener {
                 final List<PluginInfo> childList = new ArrayList<PluginInfo>();
                 sortedList.add(plugin);
                 for (final PluginInfo child : plugin.getChildren()) {
-                    childList.add(child);
+                    if (!childList.contains(child)) {
+                        childList.add(child);
+                    }
                 }
                 Collections.sort(childList);
                 sortedList.addAll(childList);